Can you make a cloud appear inside a glass jar? Real clouds form when water vapor cools and condenses onto tiny particles in the air. You can recreate that same process on a tabletop.
You add a small amount of water to a wide-mouth jar. Then you drop a lit match inside to fill the jar with smoke particles. Quickly seal the top with a heavy-duty plastic bag.
Push the bag into the jar and the air inside warms up. The jar goes clear. Pull the bag out and the air cools. Water vapor condenses onto the smoke particles and a cloud appears inside the jar.
Hypothesis
The hypothesis is that the pressure and temperature in the jar will cause the water vapor to condense and form a cloud.
Real clouds form when water vapor cools and condenses onto tiny particles in the air — and you can recreate that same process inside a glass jar. A small amount of water goes in first, then a lit match fills the jar with smoke particles. Quickly seal the top with a heavy-duty plastic bag. Push the bag into the jar and the air inside warms up, so the jar goes clear. Pull the bag out and the air cools. Water vapor condenses onto the smoke particles, and a cloud appears inside the jar.
Water vapor doesn't condense in empty air — it needs something to grab onto. In this experiment, smoke from a lit match fills the jar with tiny particles that serve exactly that purpose. Push the bag into the jar and the air inside warms, turning the jar clear. Pull it out, and the air cools rapidly. Water vapor condenses onto those smoke particles, and a visible cloud appears inside the jar.
Method & Materials
You will place water and a lit match in a jar, then quickly cover the jar with a plastic bag and secure it with a rubber band.
You will need a wide-mouth gallon pickle jar, a heavy-duty clear plastic bag, and rubber bands or masking tape.
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This experiment shows how humidity, temperature, and air pressure can influence the formation of clouds. When the bag is pushed into the jar, the pressure and temperature increase, causing the jar to clear. When the bag is pulled out, the pressure and temperature decrease, allowing the water vapor to condense and form a cloud.
Why do this project?
This science project is unique because it allows students to observe the direct effects of pressure and temperature on cloud formation.
Also Consider
Experiment variations include using a dishwashing glove (first video) or placing ice at the top of the bottle (second video), instead of the plastic bag.
Full project details
Additional information and source material for this project are available below.
These videos explain the science behind this project and demonstrate key concepts used in the experiment.
Get ready to create a cloud in a bottle that appears and disappears right before your eyes! You only need a few items to make it happen: a dishwashing glove, water, a lit match, and a glass jar. But here's the catch - if you don't use all these things, the cloud won't form. Watch as she demonstrates this by removing each item, one by one, and see what happens. It's a fun and easy experiment that you can do at home to learn about the science of clouds!
Discover the captivating science behind cloud formation! This video offers a simple and comprehensive explanation of how clouds are formed and how you can make a cloud in a bottle at home. All you need is ice cubes, hot water, food coloring, a lit match, and a glass bottle. By the end of the video, you'll have a better understanding of the amazing science that creates the clouds above us!
